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1.
Plant Dis ; 108(7): 1972-1975, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38381962

RESUMO

Polygonatum cyrtonema Hua is a perennial herb of the Asparagaceae family that is used for both dietary and medicinal purposes in China. In September 2019, a new leaf spot disease on Polygonatum cyrtonema was detected and is currently widespread in Huaihua, Hunan Province, China. Pathogenic fungi were isolated and purified from samples of diseased tissue that were collected for morphological and molecular phylogenetic studies. The pathogen was identified using multilocus (ITS, TEF-1, and TUB2) phylogenies, as well as morphological characters, and was found to be clustered but separately divergent from species of Pestalotiopsis. However, there were significant morphological differences between the pathogen and similar species. The pathogen was finally identified as a new species that was designated Pestalotiopsis xuefengensis. This is the first report of Pestalotiopsis xuefengensis serving as the causal agent of gray leaf spot on Polygonatum cyrtonema. This study will provide useful information for the diagnosis and management of this disease.


Assuntos
Filogenia , Doenças das Plantas , Polygonatum , Doenças das Plantas/microbiologia , China , Polygonatum/microbiologia , Xylariales/genética , Xylariales/classificação , Xylariales/isolamento & purificação , Folhas de Planta/microbiologia
2.
J Fungi (Basel) ; 10(3)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38535181

RESUMO

The control of Aspergillus niger (A. niger) is of great significance for the agricultural economy and food safety. In this study, the antifungal effect and mechanism of iturin A from Bacillus amyloliquefaciens (CGMCC No. 8473) against A. niger (ATCC 16404) were investigated using biochemical analyses and proteomics. Changes in a mycelium treated with iturin A were observed using scanning electron microscopy and transmission electron microscopy, including mycelial twisting and collapse, organelle disintegration, and intracellular vacuolization. The cytomembrane integrity of A. niger was affected by iturin A, as detected by propidium iodide staining. In addition, the generation of excess reactive oxygen species, the hyperpolarization of the mitochondrial membrane potential and malondialdehyde accumulation also indicated that iturin A induced apoptosis in A. niger through the oxidative stress pathway. Proteomics results showed that 310 proteins were differentially expressed in the A. niger mycelium exposed to iturin A, including 159 upregulated proteins and 151 downregulated proteins, which were mainly associated with energy metabolism of A. niger. We propose that iturin A might inhibit the growth of A. niger by disrupting cytomembrane integrity, via oxidative stress, and by interfering with glycolysis/gluconeogenesis and the tricarboxylic acid cycle. Overall, iturin A is a promising antifungal agent that provides a rationale for controlling A. niger contamination in food.

3.
PLoS One ; 19(4): e0300789, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625861

RESUMO

PURPOSE: Immunotherapy has been shown to improve cancer survival, but there are no consensus guidelines to inform use in patients with both cancer and autoimmune disease (AD). We sought to examine immunotherapy utilization patterns between cancer patients with and without AD. PATIENTS AND METHODS: This retrospective cohort study utilized data from a de-identified nationwide oncology database. Patients diagnosed with advanced melanoma, non-small cell lung cancer, and renal cell carcinoma were included. Outcomes of interest included first-line immunotherapy, overall immunotherapy, and number of immunotherapy cycles. We used logistic and Poisson regression models to examine associations between AD and immunotherapy utilization patterns. RESULTS: A total of 25,076 patients were included (796 with AD). Patients with AD were more likely to be female, White, receive care at academic centers, and have ECOG ≥ 3. Controlling for demographic and clinical variables, AD was associated with lower odds of receiving first-line (odds ratio [OR] = 0.68, 95% confidence interval [CI] 0.56-0.82) and overall (OR = 0.80, 95% CI 0.67-0.94) immunotherapy. Among patients who received at least one cycle of immunotherapy, there was no difference in mean number of cycles received between patients with and without AD (11.3 and 10.5 cycles respectively). The incident rate of immunotherapy cycles received for patients with AD was 1.03 times that of patients without AD (95% CI 1.01-1.06). DISCUSSION: Patients with AD were less likely to receive immunotherapy as first-line and overall therapy for treatment of their advanced cancer. However, among those who did receive at least one cycle of immunotherapy, patients with AD received a similar number of cycles compared to patients without AD. This not only indicates that AD is not an absolute contraindication for immunotherapy in clinical practice but may also demonstrate overall treatment tolerability and net benefit in patients with AD.


Assuntos
Doenças Autoimunes , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Renais , Neoplasias Pulmonares , Humanos , Feminino , Masculino , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Estudos Retrospectivos , Imunoterapia/efeitos adversos , Neoplasias Renais/etiologia , Doenças Autoimunes/terapia , Doenças Autoimunes/etiologia
4.
Sci Total Environ ; 946: 174229, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38917895

RESUMO

Ozone pollution is an important environmental issue in many countries. Accurate forecasting of ozone concentration enables relevant authorities to enact timely policies to mitigate adverse impacts. This study develops a novel hybrid deep learning model, named wind direction-based dynamic spatio-temporal graph network (WDDSTG-Net), for hourly ozone concentration prediction. The model uses a dynamic directed graph structure based on hourly changing wind direction data to capture evolving spatial relationships between air quality monitoring stations. It applied the graph attention mechanism to compute dynamic weights between connected stations, thereby aggregating neighborhood information adaptively. For temporal modeling, it utilized a sequence-to-sequence model with attention mechanism to extract long-range temporal dependencies. Additionally, it integrated meteorological predictions to guide the ozone forecasting. The model achieves a mean absolute error of 6.69 µg/m3 and 18.63 µg/m3 for 1-h prediction and 24-h prediction, outperforming several classic models. The model's IAQI accuracy predictions at all stations are above 75 %, with a maximum of 81.74 %. It also exhibits strong capabilities in predicting severe ozone pollution events, with a 24-h true positive rate of 0.77. Compared to traditional static graph models, WDDSTG-Net demonstrates the importance of incorporating short-term wind fluctuations and transport dynamics for data-driven air quality modeling. In principle, it may serve as an effective data-driven approach for the concentration prediction of other airborne pollutants.

5.
Curr Opin Struct Biol ; 85: 102778, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38364679

RESUMO

Since the onset of the COVID-19 pandemic in 2019, there has been a concerted effort to develop cost-effective, non-invasive, and rapid AI-based tools. These tools were intended to alleviate the burden on healthcare systems, control the rapid spread of the virus, and enhance intervention outcomes, all in response to this unprecedented global crisis. As we transition into a post-COVID era, we retrospectively evaluate these proposed studies and offer a review of the techniques employed in AI diagnostic models, with a focus on the solutions proposed for different challenges. This review endeavors to provide insights into the diverse solutions designed to address the multifaceted challenges that arose during the pandemic. By doing so, we aim to prepare the AI community for the development of AI tools tailored to address public health emergencies effectively.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , Inteligência Artificial , SARS-CoV-2 , Pandemias , Estudos Retrospectivos
6.
Int J Parasitol Parasites Wildl ; 23: 100923, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38524248

RESUMO

Eurasian lynx (Lynx lynx) is widely distributed in various habitats in Asia and Europe, and it may harbor multiple pathogens. Currently, the information on protozoan infection in Eurasian lynx is scarce. In this study, we performed nested polymerase chain reaction (nPCR) analysis to detect intestinal protozoan infection in three dead Eurasian lynxes, in northwestern China. Three dead Eurasian lynxes, an adult female (#1), an adult male (#2), and a cub male (#3), were sampled in West Junggar Mountain, the northwestern region of Xinjiang Uyghur Autonomous Region. The intestine samples were analyzed using nPCR. We used primers targeting the cytochrome C oxidase subunit I gene (COI) for detection of Sarcocystis and Eimeria species and targeting the small subunit 18 S ribosomal RNA gene (18S rRNA) for detection of Cystoisospora species. The nPCR-positive products were sequenced, aligned, and phylogenetically analyzed. Three intestinal protozoa, Sarcocystis albifronsi, Eimeria alpacae, and Cystoisospora felis, were found in three Eurasian lynxes. The intestine sample of Eurasian lynx #2 was detected with S. albifronsi and E. alpacae. In addition, C. felis was only found in the intestine sample of Eurasian lynx #3. To the best of our knowledge, S. albifronsi and E. alpacae were detected in Eurasian lynx for the first time. In addition, C. felis was firstly found in Eurasian lynx in China. These findings extend our knowledge of the geographical distribution and host range of intestinal protozoa.

7.
Cancer Med ; 13(3): e6915, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38234237

RESUMO

BACKGROUND: Treatments for multiple myeloma (MM) have evolved over time and improved MM survival. While racial differences in MM treatment and prognosis between non-Hispanic African American (NHAA) and non-Hispanic White (NHW) patients are well-established, it is unclear whether they have persisted after the introduction of novel agents. METHODS: Using the Surveillance, Epidemiology, and End Results-Medicare linked database, our study investigated racial difference in the receipt of treatment within 1 year following diagnosis and assessed survival outcomes among Medicare beneficiaries (≥66 years) diagnosed with MM from 2007 to 2017. We applied multivariable Cox proportional hazards models to estimate the association between race and survival and presented hazard ratios (HRs). RESULTS: Of 2094 NHAA and 11,983 NHW older patients with MM, 59.5% and 64.8% received treatment during the first year, respectively. Discrepancy in the proportion of patients receiving treatment between the two groups increased from 2.9% in 2007 to 2009 to 6.9% in 2014-2017. After controlling for relevant factors, patients who received treatment within the first year had lower mortality than those who did not (HR = 0.90, 95% confidence interval [CI]: 0.86-0.94). NHAA patients had a lower probability to receive treatments during the first year than NHW patients (HR = 0.91, 95% CI: 0.85-0.97) but had lower mortality (HR = 0.94, 95% CI: 0.88-1.00). The lower mortality was only observed among patients who received no treatment (HR = 0.84, 95% CI: 0.77-0.93); NHAA and NHW patients who received treatment had similar survival (p = 0.63). CONCLUSIONS: The increasing racial disparity in treatment utilization over time is concerning. Efforts are needed to eliminate the barriers of receiving treatment.


Assuntos
Disparidades em Assistência à Saúde , Mieloma Múltiplo , Idoso , Humanos , Negro ou Afro-Americano , Bases de Dados Factuais , Medicare , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Fatores Raciais , Estados Unidos/epidemiologia
8.
Int J Parasitol Parasites Wildl ; 23: 100925, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38560661

RESUMO

Red foxes (Vulpes vulpes) have been recognized as natural reservoirs for multiple pathogens and a source of infection for domestic animals, wildlife and humans. To date, no reports are available on the Bartonella rochalimae and Hepatozoon canis infection in red foxes from China. In 2018-2022, a total of 16 red foxes were sampled in two counties and a city in Xinjiang Uygur Autonomous Region (XUAR) in northwest China. Subsequently analyzed by DNA extraction amplified by polymerase chain reaction (PCR). In the present study, based on nucleotide sequence and phylogenetic tree analyses, B. rochalimae and H. canis were molecularly identified in red foxes. Our findings provide the first molecular evidence of B. rochalimae and H. canis in red foxes from China.

9.
Foods ; 13(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38472922

RESUMO

This study investigated the effects of thermosonication (TS) on the quality of blackcurrant juice, along with its physicochemical properties, bioactive compounds, antioxidant capacity, and microbiological and sensory qualities. The treatments included raw juice (RJ), pasteurized juice (90 °C, 1 min, PJ), and thermosonicated juice (480 W, 40 kHz at 40, 50, or 60 °C, for 10, 20, 30, or 40 min, TJ). The results indicated that the effects of pasteurization and thermosonication on the pH, total soluble solids, and titratable acidity of the juice were not significant (p > 0.05). However, the cloudiness, browning index, and viscosity were significantly increased (p < 0.05), and the color properties of the blackcurrant juice were improved. The total phenolic, flavonoid, and anthocyanin contents of TJ (treated at 50 °C for 30 min) were increased by 12.6%, 20.9%, and 40.4%, respectively, and there was a notable decline in ascorbic acid content after the pasteurization treatment, while the loss was minor in all TJ samples compared with RJ. The scavenging ability of 1,1-diphenyl-2-pyridyl and hydroxyl radicals increased to 52.77% and 50.52%, respectively, which were significantly (p < 0.05) higher than those in the RJ and PJ samples. In addition, both pasteurization and thermosonication resulted in a significant (p < 0.05) reduction in microbial counts, while there were no significant (p > 0.05) differences in the sensory parameters compared with the RJ samples. In conclusion, this study suggests that TS is an effective method that can be used as an alternative to pasteurization to improve the quality of blackcurrant juice.

10.
Huan Jing Ke Xue ; 45(6): 3389-3401, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897760

RESUMO

Clarifying the mechanism of influence of urban form on carbon emissions is an important prerequisite for achieving urban carbon emission reduction. Taking the Yangtze River Economic Belt as an example, this study elaborated on the general mechanism of urban form on carbon emissions, used multi-source data to quantitatively evaluate the urban form, and explored the impacts of urban form indicators on carbon emissions from 2005 to 2020 at global and sub-regional scales with the help of spatial econometric models and geodetector, respectively. The results showed that:① The carbon emissions of the Yangtze River Economic Belt increased from 2 365.31 Mt to 4 230.67 Mt, but the growth rate gradually decreased. Its spatial distribution pattern was bipolar, with high-value areas mainly distributed in core cities such as Shanghai and Chongqing and low-value areas concentrated in the western regions of Sichuan and Yunnan. ② The area of construction land in the study area expanded over the past 15 years, but the population density of construction land had been decreasing. The degree of urban fragmentation was decreasing, and the difference between cities was also progressively narrowing. The average regularity of urban shape improved, and the compactness increased significantly. ③ All indicators of urban scale had significant positive effects on carbon emissions at the global scale, urban fragmentation had a significant negative effect in 2005, and the effective mesh size (MESH) indicator of urban compactness showed a significant negative correlation with carbon emissions in the study period. ④ Total class area, patch density, and effective mesh size had the most significant impacts on carbon emissions in upstream cities. Effective mesh size, mean perimeter-area ratio, and total class area had higher influences in midstream cities. Effective mesh size, percentage of like adjacencies, and largest patch index were the key factors to promote carbon reduction in downstream cities. Cities in different regions should comprehensively consider the impacts of various urban form indicators on carbon emissions and then optimize their urban form to promote sustainable development.

11.
Chemosphere ; 356: 141942, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588893

RESUMO

Covalent organic frameworks (COFs) demonstrate remarkable potential for adsorbing per/polyfluoroalkyl substances (PFAS). Nevertheless, the challenge of recycling powdered COFs hampers their practical application in water treatment. In this research, a quaternary amine COF with inherent positive surface charge was synthesised to adsorb perfluorooctanoic acid (PFOA) via electrostatic interactions. The COF was then combined with chitosan (CS) through a simple dissolution-evaporation process, resulting in a composite gel material termed COF@CS. The findings indicated that the adsorption capacity of COF@CS significantly surpassed that of the original COF and CS. According to the Langmuir model, COF@CS achieved a maximum PFOA capacity of 2.8 mmol g-1 at pH 5. Furthermore, the adsorption rate increased significantly to 6.2 mmol g-1 h-1, compared to 5.9 mmol g-1 h-1 for COF and 3.4 mmol g-1 h-1 for CS. Notably, COF@CS exhibited excellent removal efficacy for ten other types of PFAS. Moreover, COF@CS could be successfully regenerated using a mixture of 70% ethanol and 1 wt% NaCl, and it exhibited stable reusability for up to five cycles. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) characterisation, and theoretical calculations revealed that the quaternary amine functional group in COF served as the primary adsorption site in the composite gel material, while the protonated amino group on CS enhanced PFOA adsorption through electrostatic interaction. This study highlights the significant practical potential of COF@CS in the removal of PFAS from aqueous solution and environmental remediation.


Assuntos
Caprilatos , Quitosana , Fluorocarbonos , Estruturas Metalorgânicas , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Adsorção , Poluentes Químicos da Água/química , Fluorocarbonos/química , Purificação da Água/métodos , Caprilatos/química , Estruturas Metalorgânicas/química
12.
J Wildl Dis ; 60(3): 792-794, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38659240

RESUMO

Anaplasma bovis (1), Bartonella krasnovii (3), and Bartonella sp. (17) were detected in 80 Libyan jirds (Meriones libycus) from China. These findings extend the known host and geographic ranges of these pathogens, with neither A. bovis nor B. krasnovii previously confirmed in Libyan jirds.


Assuntos
Anaplasma , Anaplasmose , Infecções por Bartonella , Bartonella , Animais , China/epidemiologia , Anaplasma/isolamento & purificação , Bartonella/isolamento & purificação , Infecções por Bartonella/veterinária , Infecções por Bartonella/epidemiologia , Infecções por Bartonella/microbiologia , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Roedores/microbiologia , Feminino , Masculino
13.
Microbiol Res ; 287: 127858, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39106786

RESUMO

Neurotransmitters, including 5-hydroxytryptamine (5-HT), dopamine (DA), gamma-aminobutyric acid (GABA), and glutamate, are essential transductors in the Gut-Brain Axis (GBA), playing critical roles both peripherally and centrally. Accumulating evidence suggests that the gut microbiota modulates intestinal neurotransmitter metabolism and gut-to-brain signaling, shedding light on the crucial role of the gut microbiota in brain function and the pathogenesis of various neuropsychiatric diseases, such as major depression disorder (MDD), anxiety, addiction and Parkinson's disease (PD). Despite the exciting findings, the mechanisms underlying the modulation of neurotransmitter metabolism and function by the gut microbiota are still being elucidated. In this review, we aim to provide a comprehensive overview of the existing knowledge about the role of the gut microbiota in neurotransmitter metabolism and function in animal and clinical experiments. Moreover, we will discuss the potential mechanisms through which gut microbiota-derived neurotransmitters contribute to the pathogenesis of neuropsychiatric diseases, thus highlighting a novel therapeutic target for these conditions.


Assuntos
Eixo Encéfalo-Intestino , Encéfalo , Microbioma Gastrointestinal , Neurotransmissores , Transdução de Sinais , Microbioma Gastrointestinal/fisiologia , Neurotransmissores/metabolismo , Humanos , Eixo Encéfalo-Intestino/fisiologia , Animais , Encéfalo/metabolismo , Transtornos Mentais/microbiologia , Transtornos Mentais/metabolismo , Transtornos Mentais/fisiopatologia , Dopamina/metabolismo , Serotonina/metabolismo
14.
Front Endocrinol (Lausanne) ; 15: 1347684, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38524632

RESUMO

Introduction: Global phase III clinical trials have shown superior hypoglycemic efficacy to insulin and other oral hypoglycemic agents. However, there is a scarcity of real-world data comparing different glucagon-like peptide 1 receptor agonist (GLP-1RA) directly. This study aimed to assess the safety and effectiveness of various GLP-1RA in treating type 2 diabetes mellitus (T2DM) in a real-world clinical setting and identify predictive factors for favorable treatment outcomes. Methods: This was a retrospective, single-center, real-world study. The changes in HbA1c, fasting plasma glucose (FPG), body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), and the percentage of participants who achieved HbA1c of <7%, 7%-8%, and ≥ 8% after GLP-1RA treatment was analyzed. The clinical factors that affect the effectiveness of GLP-1RA were analyzed. Results: At baseline, the 249 participants had a mean baseline HbA1c of 8.7 ± 1.1%. After at least three months of follow-up, the change in HbA1c was -0.89 ± 1.3% from baseline. Dulaglutide exerted a more significant hypoglycemic effect than immediate-release exenatide. The percentage of participants who achieved HbA1c<7% was substantial, from 6.0% at baseline to 28.9%. Average body weight decreased by 2.02 ± 3.8 kg compared to baseline. After GLP-1RA treatment, the reduction in SBP was 2.4 ± 7.1 mmHg from baseline. A shorter duration of diabetes and a higher baseline HbA1c level were more likely to achieve a good response in blood glucose reduction. Conclusions: This study provided real-world evidence showing that GLP-1RA significantly improved HbA1c, body weight, and SBP. The results can inform the decision-making about GLP-1RA treatment in daily clinical practice.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Glicemia , Peso Corporal , Peptídeo 1 Semelhante ao Glucagon/agonistas , Hemoglobinas Glicadas , Hipoglicemiantes/uso terapêutico , Estudos Retrospectivos
15.
Parasit Vectors ; 17(1): 152, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519971

RESUMO

BACKGROUND: In the family Trypanosomatidae, the genus Trypanosoma contains protozoan parasites that infect a diverse range of hosts, including humans, domestic animals, and wildlife. Wild rodents, as natural reservoir hosts of various pathogens, play an important role in the evolution and emergence of Trypanosomatidae. To date, no reports are available on the trypanosomatid infection of pikas (Lagomorpha: Ochotonidae). METHODS: In this study, Mongolian pikas and their fleas were sampled at the China-Mongolia border, northwestern China. The samples were analyzed with polymerase chain reaction (PCR) and sequencing for the presence of Trypanosomatidae on the basis of both the 18S ribosomal RNA (18S rRNA) gene and the glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) gene. The morphology of trypomastigotes was also observed in peripheral blood smears by microscopy. RESULTS: Molecular and phylogenetic analyses revealed a new genotype of the Trypanosoma lewisi clade that was found both in pika blood and flea samples. This genotype, which probably represents a new species, was provisionally designated as "Trypanosoma sp. pika". In addition, a novel genotype belonging to the genus Blechomonas of Trypanosomatidae was detected in fleas. On the basis of its molecular and phylogenetic properties, this genotype was named Blechomonas luni-like, because it was shown to be the closest related to B. luni compared with other flea-associated trypanosomatids. CONCLUSIONS: To the best of our knowledge, this is the first study to report any trypanosomatid species in Mongolian pikas and their fleas. Further studies are needed to investigate the epidemiology of these protozoan parasites, as well as to evaluate their pathogenicity for humans or domestic animals.


Assuntos
Lagomorpha , Sifonápteros , Trypanosoma , Trypanosomatina , Animais , Humanos , Lagomorpha/parasitologia , Sifonápteros/parasitologia , Filogenia , China/epidemiologia , Trypanosoma/genética , Trypanosomatina/genética , Animais Domésticos , Gerbillinae
16.
Neuron ; 112(10): 1657-1675.e10, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38574730

RESUMO

Astrocytes strongly promote the formation and maturation of synapses by secreted proteins. Several astrocyte-secreted synaptogenic proteins controlling excitatory synapse development were identified; however, those that induce inhibitory synaptogenesis remain elusive. Here, we identify neurocan as an astrocyte-secreted inhibitory synaptogenic protein. After secretion from astrocytes, neurocan is cleaved into N- and C-terminal fragments. We found that these fragments have distinct localizations in the extracellular matrix. The neurocan C-terminal fragment localizes to synapses and controls cortical inhibitory synapse formation and function. Neurocan knockout mice lacking the whole protein or only its C-terminal synaptogenic domain have reduced inhibitory synapse numbers and function. Through super-resolution microscopy, in vivo proximity labeling by secreted TurboID, and astrocyte-specific rescue approaches, we discovered that the synaptogenic domain of neurocan localizes to somatostatin-positive inhibitory synapses and strongly regulates their formation. Together, our results unveil a mechanism through which astrocytes control circuit-specific inhibitory synapse development in the mammalian brain.


Assuntos
Astrócitos , Neurocam , Sinapses , Animais , Humanos , Camundongos , Astrócitos/metabolismo , Células Cultivadas , Camundongos Knockout , Neurocam/metabolismo , Somatostatina/metabolismo , Sinapses/metabolismo , Sinapses/fisiologia
17.
Antioxidants (Basel) ; 13(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38671916

RESUMO

Oxidative stress causes gut dysfunction and is a contributing factor in several intestinal disorders. Intestinal epithelial cell survival is essential for maintaining human and animal health under oxidative stress. 18beta-Glycyrrhetinic acid (GA) is known to have multiple beneficial effects, including antioxidant activity; however, the underlying molecular mechanisms have not been well established. Thus, the present study evaluated the therapeutic effects of GA on H2O2-induced oxidative stress in intestinal porcine epithelial cells. The results showed that pretreatment with GA (100 nM for 16 h) significantly increased the levels of several antioxidant enzymes and reduced corresponding intracellular levels of reactive oxidative species and malondialdehyde. GA inhibited cell apoptosis via activating the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway, as confirmed by RNA sequencing. Further analyses demonstrated that GA upregulated the phosphorylation levels of PI3K and Akt and the protein level of B cell lymphoma 2, whereas it downregulated Cytochrome c and tumor suppressor protein p53 levels. Moreover, molecular docking analysis predicted the binding of GA to Vasoactive intestinal peptide receptor 1, a primary membrane receptor, to activate the PI3K/Akt signaling pathway. Collectively, these results revealed that GA protected against H2O2-induced oxidative damage and cell apoptosis via activating the PI3K/Akt signaling pathway, suggesting the potential therapeutic use of GA to alleviate oxidative stress in humans/animals.

18.
Artif Intell Med ; 154: 102930, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39047631

RESUMO

In the realm of pulmonary tracheal segmentation, the scarcity of annotated data stands as a prevalent pain point in most medical segmentation endeavors. Concurrently, most Deep Learning (DL) methodologies employed in this domain invariably grapple with other dual challenges: the inherent opacity of 'black box' models and the ongoing pursuit of performance enhancement. In response to these intertwined challenges, the core concept of our Human-Computer Interaction (HCI) based learning models (RS_UNet, LC_UNet, UUNet and WD_UNet) hinge on the versatile combination of diverse query strategies and an array of deep learning models. We train four HCI models based on the initial training dataset and sequentially repeat the following steps 1-4: (1) Query Strategy: Our proposed HCI models selects those samples which contribute the most additional representative information when labeled in each iteration of the query strategy (showing the names and sequence numbers of the samples to be annotated). Additionally, in this phase, the model selects the unlabeled samples with the greatest predictive disparity by calculating the Wasserstein Distance, Least Confidence, Entropy Sampling, and Random Sampling. (2) Central line correction: The selected samples in previous stage are then used for domain expert correction of the system-generated tracheal central lines in each training round. (3) Update training dataset: When domain experts are involved in each epoch of the DL model's training iterations, they update the training dataset with greater precision after each epoch, thereby enhancing the trustworthiness of the 'black box' DL model and improving the performance of models. (4) Model training: Proposed HCI model is trained using the updated training dataset and an enhanced version of existing UNet. Experimental results validate the effectiveness of this Human-Computer Interaction-based approaches, demonstrating that our proposed WD-UNet, LC-UNet, UUNet, RS-UNet achieve comparable or even superior performance than the state-of-the-art DL models, such as WD-UNet with only 15 %-35 % of the training data, leading to substantial reductions (65 %-85 % reduction of annotation effort) in physician annotation time.


Assuntos
Aprendizado Profundo , Humanos , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Inteligência Artificial , Traqueia/diagnóstico por imagem
19.
Bioresour Technol ; 406: 131061, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38960005

RESUMO

Starch is an attractive feedstock in biorefinery processes, while the low natural conversion rate of most microorganisms limits its applications. Herein, starch metabolic pathway was systematically investigated using Bacillus licheniformis DW2 as the host organism. Initially, the effects of overexpressing amylolytic enzymes on starch hydrolysis were evaluated. Subsequently, the transmembrane transport system and intracellular degradation module were modified to accelerate the uptake of hydrolysates and their further conversion to glucose-6-phosphate. The DW2-derived strains exhibited robust growth in starch medium, and productivity of bacitracin and subtilisin were improved by 38.5% and 32.6%, with an 32.3% and 22.9% increase of starch conversion rate, respectively. Lastly, the employment of engineering strategies enabled another B. licheniformis WX-02 to produce poly-γ-glutamic acid from starch with a 2.1-fold increase of starch conversion rate. This study not only provided excellent B. licheniformis chassis for sustainable bioproduction from starch, but shed light on researches of substrate utilization.


Assuntos
Bacillus licheniformis , Amido , Amido/metabolismo , Bacillus licheniformis/metabolismo , Hidrólise , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/biossíntese , Microbiologia Industrial/métodos
20.
Dalton Trans ; 53(6): 2619-2625, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38224003

RESUMO

Birefringent materials play an important role in laser techniques as an essential part of optical devices. Therefore, the exploration of high-performance birefringent materials has been a central focus of researchers. Herein, two tin(II) fluoride oxalates Na4Sn4(C2O4)3F6 and NaSnC2O4F·H2O were gained by the combination of birefringence-active groups of Sn2+ with stereochemically active lone pairs and planar π-conjugated [C2O4]2- groups. These groups assemble into low-dimensional structures of 0D [C2O4F4]6- clusters and 1D [SnC2O4F]∞- chains in Na4Sn4(C2O4)3F6, and double [Sn2(C2O4)2F2]∞2- chains in NaSnC2O4F·H2O, which gives rise to the large birefringence of 0.160@546 nm and 0.189@546 nm, respectively. Detailed structure-property analysis and theoretical calculations indicate that strong optical anisotropy can be induced by the rational arrangement of the Sn2+-polyhedra and [C2O4]2- groups.

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